I agree. Joe should never shoot a 100 year old damascus gun. End of discussion.

As to the OP, shooting the gun likely pulled every minute trace of oil out of the barrels, making more of the small pitting evident. It was always there. Freshly oiled bores will often mask fine pitting, making it hard to detect unless it is VERY thoroughly cleaned out with alcohol (or shooting).

“I left long before daylight, alone but not lonely.”~Gordon Macquarrie